Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University, where she is the director of the Yale Center for Astronomy and Astrophysics.

Since its launch four years ago, Kepler has found more than 2,700 possible planets orbiting stars other than our Sun, of which more than 100 have been confirmed. A few of these exoplanets resemble the Earth in size or mass.

Recently, three Earth-like planets were even reported to be in the habitable zone: close enough to the star they orbit that water is liquid, yet not so close that it is boiling. Planets with liquid water may well harbor life.

Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University, where she is the director of the Yale Center for Astronomy and Astrophysics

On April 27, NASA's Fermi and Swift satellites detected a strong signal from the brightest gamma-ray burst in decades. Because this was relatively close, it was thousands of times brighter than the typical gamma-ray bursts that are seen by Swift every few days. Scientists are now scrambling to learn more.

We already knew that when the biggest stars run out of fuel, they don't fade quietly away. Instead, they explode in a blaze of glory known as a supernova. These stellar explosions are often bright enough to be seen by us even though they are in galaxies billions of light-years from our own Milky Way galaxy home.

In very rare cases - such as GRB130427A (tagged with the date of its discovery) - astrophysicists are lucky enough to see energetic gamma-rays from hyperfast jets of outflowing material consisting of charged particles created during a massive star's violent death throes.

For millennia, humans have gazed at the night sky, asking this question. That's why scientists and NASA are eagerly searching for "exoplanets" - that is, planets that orbit around stars other than our sun.

Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University, where she is the director of the Yale Center for Astronomy and Astrophysics.

(CNN) - In 2001, I became the first tenured female faculty member ever in Yale's physics department. Throughout my 30 years as a physicist, being the only woman in the room has been the norm. Women fill more than half of the jobs in the U.S. economy but constitute fewer than 12% of working physicists and engineers. For me and for others in STEM fields (science, technology, engineering and mathematics), the dearth of women is not news.

Evidence shows that established scientists at top research universities - those choosing and training the next generation of STEM experts - unconsciously rate budding female scientists lower than men with identical credentials. They judge women less capable, less worthy of hiring and less deserving of mentoring. And they propose starting salaries that are on average 14% higher for men than for women.

Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University, where she is the director of the Yale Center for Astronomy and Astrophysics. This article was written in association with the Op-Ed Project.

Anchorage, Alaska (CNN) - In Ballroom E of the Den'aina conference center here Wednesday, a small group of astronomers and journalists listened to the NASA feed from Kwajalein island, between Hawaii and Australia, where a Pegasus rocket aboard an L1011 plane was about to launch the NuSTAR space telescope. I was there as a member of the science team for NuSTAR, which is part of NASA's Small Explorer program

Many years in the making, NuSTAR carries an important scientific instrument designed to look for energetic X-rays from cosmic sources like black holes and exploded stars.

Most of us know about X-rays used for diagnostic imaging of broken limbs or for security scans at the airport. They are a high-energy form of light, energetic enough to penetrate clothing or flesh.

Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University. She is also the director of the Yale Center for Astronomy and Astrophysics. She previously worked as a senior astronomer at the Space Telescope Science Institute, which runs the Hubble Space Telescope for NASA. This piece was written in association with The Op-Ed Project, an organization seeking to expand the range of opinion voices to include more women.

Nearly everyone I meet has heard of the Hubble Space Telescope. Many have seen its beautiful images of the birthplace of new stars and planetary systems, or of the "gravitational lenses" that reveal a mysterious "dark matter" that dwarfs the amount of matter bound up in stars or galaxies.

This year's Nobel Prize in physics went to three scientists who used Hubble to detect the mysterious dark energy - a sort of fifth fundamental force, previously unknown - that we now think is causing the accelerated expansion of the universe.

Hubble pictures and the knowledge the HST generates have changed our view of the cosmos and reached nearly every schoolchild in America.

Editor's note: Meg Urry is the Israel Munson professor of physics and astronomy and chairwoman of the department of physics at Yale University, where she is the director of the Yale Center for Astronomy and Astrophysics. This piece was written in association with The Op-Ed Project, an organization seeking to expand the range of opinion voices to include more women.

Last weekend, another large piece of "space junk" tumbled to Earth, perhaps in Southeast Asia. Many people - if they noted the event at all - probably worried about being hit on the head, even though the odds are overwhelmingly against such a catastrophe (trillions to one).

But for thousands of astrophysicists around the world, the German Roentgen satellite ("ROSAT") was no mere rubbish; it was an old and important friend. Launched in 1990, a few months after the better known Hubble Space Telescope, ROSAT provided images of the sky in X-rays (very short wavelength light), as opposed to the red-green-blue light visible with Hubble, meaning it could see the most energetic phenomena in the Universe. Plus ROSAT had better image quality than any X-ray satellite had before, an improvement comparable to the superiority of Hubble imaging compared to ground-based telescopes.

A few thousand astronomers worldwide used ROSAT to study the universe, discovering where black holes are growing, when massive clusters of galaxies formed, and how neutron stars and black holes in our Milky Way Galaxy behave.

Astronomers just discovered the largest reservoir of water ever, roughly 140 trillion times the volume of the Earth's oceans. With severe drought afflicting Africa, Asia and the southern United States, you might ask whether this offers a solution to earthly afflictions.

Alas, it is in the very distant universe, roughly 12 billion light years from Earth. So even moving at light speed (NASA's fastest spacecraft move about 20,000 times slower), it would take humans several trillion lifetimes to reach this water blob, never mind bringing it home - definitely too far for a quick trip to the well.

But it's worth taking a deeper look. The newly discovered water can teach us about the universe when it was only a fraction of its present age.

Editor's note:Meg Urry is director of the Yale Center for Astronomy & Astrophysics and the chair of the Yale physics department. Her nearly three-decade career of space study includes a 14-year stint at the the Space Telescope Science Institute, the home of the Hubble Space Telescope, where she headed the Space Science Selection Office, sifting through thousands of applications from scientists each year hoping to use the telescope. This piece was written in association with The Op-Ed Project, an organization seeking to expand the range of opinion voices to include more women.

(CNN) - Atlantis, the last space shuttle, returned to Earth on Thursday and will go to its post-retirement gig at the Kennedy Space Center Visitor Complex. After more than 30 years and 135 shuttle flights by literally hundreds of astronauts, NASA has reason to be proud.

But for any terrestrial mourners out there, I have some tissues and another perspective: It's time.

The shuttle is an aging workhorse that should be put to pasture - it's time for a new direction for the space program.

The private sector should take over routine spaceflight while NASA develops new, more technologically current vehicles that can carry human explorers well beyond low Earth orbit.

Just as importantly, NASA should continue its wildly successful program of robotic space science, which has returned an incredible wealth of knowledge for pennies on the human-spaceflight dollar.

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